OpenTerminal v0.2.1: terminal suite with SSH, split panes, themes and keyword highlighting

- Local terminal (node-pty) + SSH sessions (ssh2) with unified data plane
- dockview split panes, per-group '+' tab bar button, layout templates
- Session replay buffer (late-subscriber catch-up), host key pinning,
  credential encryption via safeStorage
- 12 builtin themes + custom theme editor, system font enumeration
- Keyword highlighting: regex rules with priority, ANSI truecolor injection,
  chunk-boundary-safe stream (carry-over of partial escape sequences)
- Dark antd theme app-wide, settings dialog redesign, error boundary
- Tests: ssh loopback, session e2e, highlight split-chunk regression

tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "files": [],
+  "references": [
+    { "path": "./tsconfig.node.json" },
+    { "path": "./tsconfig.web.json" }
+  ]
+}